Whole in the Water
Well-Known Member
All the more reason for us to unite to work to get more fish in the ocean. Otherwise we will just end up fighting over who gets how much as the salmon populations continue to decline!
I gave you the email address and the phone number of Ken Pearce a Co-Chair of Seal Impact in a recent previous post, so please contact him and give him your support.
I have worked with Ken Pearce on several DFO issues for the past year or so and I know from his track record that he will add a new dimension to this mess that we find ourselves. With Ken leading the charge this group is going to get some action and be responsible for some major changes to the way our fishery is being managed in the years ahead. This is a one time, great opportunity to initiate some badly needed changes and Ken and his group are the real deal, so please give Ken and his group your full support. Nothing on this scale has ever been done before.
great questions and observations, ziggy! The sound intensity also has an impact. I think whales/marine mammals can also get accustomed to some sounds.
Humpbacks talk in the 100-350Hz range; but can hear in the 30-8,000Hz range. Toothed whales (e.g. orcas) have best frequency of hearing between 80 and 150 kHz and maximum sensitivity between 40-50 dB - but can hear in the 80-25,000Hz range; often talking in the 6,000-12,000Hz range. Seals, on the other hand typically have a high-frequency cutoff in their underwater hearing between 30 and 60 kHz, and maximal sensitivity of about 60 dB; but listen in the 100-40,000Hz range.
What about the sound sources - intensities and frequencies?
Sounders typically operate in the 50-200KHz range; or 50,000 to 200,000Hz range at 250-500Watts. Not sure how watts translate into dBs; but 140dB = 100watts/m2 - and the sound is radiated downwards towards the bottom in a narrow cone of 10-20 degrees. It wouldn't be too many meters below the boat when the sound energy decreases exponentially - and more importantly - The frequency is far above most marine mammals hearing ability.
A zodiac/outboard transmits sound in the 5000-6,300Hz range at ~150dB at source; while a tanker 100-225Hz range at ~180dB at source. SOURCE: Richardson et al. (1995). https://www.sciencedirect.com/science/book/9780080573038
A 195dB noise at source will be attenuated to ~129dB at 2km in the ocean; a 180dB noise will generate a response from marine mammals at 5km, but be undetectable within background noise at ~45km.
Thanks AA. I read another article that suggested the Orca hears best at 20-40 kHz and echolocates in the 20K range. In addition here is an interesting onegreat questions and observations, ziggy! The sound intensity also has an impact. I think whales/marine mammals can also get accustomed to some sounds.
Humpbacks talk in the 100-350Hz range; but can hear in the 30-8,000Hz range. Toothed whales (e.g. orcas) have best frequency of hearing between 80 and 150 kHz and maximum sensitivity between 40-50 dB - but can hear in the 80-25,000Hz range; often talking in the 6,000-12,000Hz range. Seals, on the other hand typically have a high-frequency cutoff in their underwater hearing between 30 and 60 kHz, and maximal sensitivity of about 60 dB; but listen in the 100-40,000Hz range.
What about the sound sources - intensities and frequencies?
Sounders typically operate in the 50-200KHz range; or 50,000 to 200,000Hz range at 250-500Watts. Not sure how watts translate into dBs; but 140dB = 100watts/m2 - and the sound is radiated downwards towards the bottom in a narrow cone of 10-20 degrees. It wouldn't be too many meters below the boat when the sound energy decreases exponentially - and more importantly - The frequency is far above most marine mammals hearing ability.
A zodiac/outboard transmits sound in the 5000-6,300Hz range at ~150dB at source; while a tanker 100-225Hz range at ~180dB at source. SOURCE: Richardson et al. (1995). https://www.sciencedirect.com/science/book/9780080573038
A 195dB noise at source will be attenuated to ~129dB at 2km in the ocean; a 180dB noise will generate a response from marine mammals at 5km, but be undetectable within background noise at ~45km.
Who exactly is Ken Pearce and his group?We are entering a whole new era in our fight against the ongoing total incompetence and ineptitude of the DFO as they gradually take our fishery to the brink of extinction. Enough is enough. Ken Pearce and his group are going to lead the charge against this enormous mess that the politically manipulated DFO have created. It is not going to be an easy fight but I have faith that we have assembled a very powerful group of well informed smart stakeholders who will be able to make some significant changes in the way that our fishery is being managed. You have to ask yourself what is going on here and what can be done to correct a flawed, dysfunctional, poorly managed DFO? Please support Ken and his group as they are our only chance of changing a fishery management system that is not working.
Your throwing in the towel, BM? I know you still got some fight left in you?I wouldn't waste anymore time on this, fishing is over.
If they are proposing closing down langara island to Rose spit for NRKW that would include some of the biggest and most expensive lodges on the Coast ( langara, WCFC, QC lodge) They already will be impacted by the reduced limits. As some guests might not be so keen to pay 6k to keep 2 chinook and 2 small halibut. I would think they are mobilizing resources to fight it. There are killer whales in that area a lot.
Not sure if forming another group makes much sense!?
It doesn't. But it gives someone the opportunity to gain power, prestige, influence and standing.
Better off joining the envirobullies like the Raincoast Conservation Foundation, and then completely subverting them with a #feedthewhales campaign. It would be very easy to run an insurrection of these groups. Infiltrate & indoctrinate, then have a bloodless coup. Next thing you know, you have their troops protesting salmon farms and demanding money for bullwhip kelp nurseries, and their social media influence on the general population.
Thanks AA. I read another article that suggested the Orca hears best at 20-40 kHz and echolocates in the 20K range. In addition here is an interesting one
https://asa.scitation.org/doi/abs/10.1121/1.427121